pub fn test() {
    let integer = 3u32;
    let boolean = true;
    let unit = ();

    let copied_integer = integer;

    println!("An integer: {:?}", copied_integer);
    println!("A boolean: {:?}", boolean);
    println!("Meet the unit value: {:?}", unit);
    let immutable = 3;
    let mut mutable = 3;
    mutable += immutable;
    println!("{}", mutable);
}
